ABSTRACT
In this chapter we present mathematical models for calculating the vector fields for Gaussian beams passing through a spatially limiting aperture. Two vector diffraction theories are presented:
Gaussian Hertz vector diffraction theory (GHVDT), and
Luneherg's vector diffraction theory for Gaussian beams
GHVDT is valid for all points within and beyond the diffracting aperture. Luneberg's model is mathematically simpler, but invalid for points: within the aperture plane, or very close to it. Additionally, we present an analytical model that enables the user to quickly calculate a diffracted Gaussian laser beam's electric field and intensity along the optical axis. In the last section we present some experimental measurements of diffracted Gaussian laser beams, and compare the results to those, predicted by the models presented in this chapter.
